Introduction

The Headwaters Small Stream Restoration Project involves 5.25 stream miles, located on North Fork (.7 mile) and South Fork (2.2 miles) Limber Jim Creeks (tributaries to Limber Jim Creek); Dry Creek (1.6 miles) and Sheep Creek Trib (.75 mile) (tributaries to Sheep Creek).  The project is located within Limber Jim Subwatershed (170601040102), and Sheep Creek Subwatershed (170601040105).  All of the streams above have summer steelhead and redband trout habitat except for the Sheep Creek tributary stream. South Fork Limber Jim has habitat for spring/summer chinook habitat.  All of the streams go partially dry during the summer/early fall except for North Fork Limber Jim Creek and the Sheep Creek tributary stream.  Historic beaver trapping, timber harvest, grazing, and roading created a laterally confined channel, with limited floodplain interaction and diminished deciduous vegetation.

The project would prioritize LWD placement (channel spanning log jams, whole trees and small wood material) to add roughness, increase floodplain interaction and habitat complexity, and promote out of channel flooding.  Partners include Grande Ronde Model Watershed, Bonneville Power Administration, and the US Forest Service.

Issues

The small streams and its meadow habitats are not in proper functioning ecological condition (hydrologic, geomorphic, vegetative composition), due to historic management that included beaver trapping, over grazing, logging, road building, and an altered fire regime.

Floodplain form and function/habitat complexity - The small streams' floodplains have limited water capture and retention capacities due to past anthropogenic influences.  These deficiencies have lowered ground tables.  This has resulted in lower riparian vegetation survival and vigor, a decreased ability to store water and buffer water temperature, less connection to the floodplain to moderate in-channel velocity, and lower quality fish habitat.

Lack of floodplain form and function has resulted in:

*  decrease in water storage and meadow/wetland habitats, resulting in drier site and mesic-site species encroachment. Drier habitats are less conducive to riparian deciduous woody vegetation species (Populous and Salix) that are important food and habitat for beaver populations.

*  potential increase of in-stream water temperatures from decrease in groundwater recharge, which can be problematic for salmonids.

*  increase of in-channel velocity where the channel has downcut, and doesn't spread water out onto the floodplain during high flows.   The process of downcutting causes vertical erosion, which increases fine sediment levels and decreases habitat complexity.

*  decrease in the amount of zero velocity habitat, which provide juvenile salmonids protection, temperature buffering, food sources and feeding areas, and resting areas.

Objectives

To achieve proper ecological form and function of the small streams and its meadows, and thereby restore habitat for the imperiled Snake River Basin Spring/Summer Chinook and Snake River Basin Steelhead.

*  Restore Hydrologic Function Increase hydration of laterally confined channel to improve groundwater retention. Use Large Woody Debris (LWD) to restore stream grade, reduce hydraulic efficiencies, and increase floodplain meadow inundation time.  LWD structures will be placed in locations to increase roughness and back up water.

*  Improve Fish Habitat Restore channel habitat complexity. Structures will enhance pools, cover and floodplain connection. The structures will increase hydraulic complexity and zero velocity refugia on active channel margins. LWD structure types designed to meet fish habitat goals include: channel spanning structures to back water into pool habitat and small wood and whole tree placements.

It is expected that the project will promote longer periods of hydrologic production, decreased stream temperatures, and increased riparian deciduous vegetation.

Benefits include the following:

*  Deflect water into the floodplain for groundwater storage (hyporheic activity) and off channel fish habitat.
*  Back water into existing fish habitat structures.
*  Recruit fluvially sorted wood.
*  Promote gravel deposition and spawning gravel recruitment.
*  Recruit deciduous vegetation by increasing groundwater storage.
*  Improve habitat for future use by beaver populations.
*  Decrease conifer encroachment in meadow habitats.